Apparatus for centering bands of lightsensitive material or the like



June 11 1968 R, KOEHLER ETAL 3,387,760

APPARATUS FOR CENTERING BANDS OF LIGHT-SENSITIVE MATERIAL OR THE LIKE Filed Dec. 15, 1966 I5 Sheets-Sheet 1 IN VEN TOR.

ROLAND KQHLER y WILHELM BAASNER ERICH NAGEL GUNTER ENGELAGE I7L1I dlizf \/I [97):1

June 11, 1968 R. KOEHLER ETAL 3,387,760

APPARATUS FOR CENTERING BANDS 0F LIGHT-SENSITIVE MATERIAL OR THE LIKE Filed Dec. 15-, 1966 5 Sheets-Sheet INVENTOR.

ROLAND KUHLER BY WILHELM BAASNER ERICH NAGEL GUNTER ENGELAGE ,ua'mz J. \f/nkc,"

June 11, 1968 R. KOEHLER ETAL APPARATUS FOR CENTERING BANDS OF LIGHT-SENSITIVE MATERIAL OR THE LIKE Filed Dec. 15, 1966 5 Sheets-Sheet 3 INVENTOR.

ROLAND KOHLER WILHELM BAASNER ERICH NAGEL GUNTER ENGELAGE ,1; J a a J: Jfn' IL,

United States Patent 3,387,760 APPARATUS FOR CENTERING BANDS OF LIGHT- SENSITIVE MATERIAL OR THE LIKE Roland Koehler and Wilhelm Baasner, Munich, Erich Nagel, Anzing, and Guenter Engelage, Unterhaching, Munich, Germany, assignors to Agfa-Gevaert Aktiengesellschaft, Leverkusen, Germany Filed Dec. 15, 1966, Ser. No. 602,017 Claims priority, application Germany, Dec. 24, 1965, A 51,176 27 Claims. (Cl. 226-198) The present invention relates to an apparatus for centering bands of light-sensitive paper or the like. More particularly, the invention relates to a centering apparatus which may be utilized in photographic copying machines to guide bands of light-sensitive paper in a predetermined path.

In photographic copying machines, the central symmetry plane of light-sensitive paper must coincide with the optical axis of the machine. Otherwise, the prints produced in such machines will have blank edges of different width and the edges must be trimmed in a subsequent operation which consumes time and necessitates the provision of additional equipment. Therefore, each photographic copying machine normally comprises a centering apparatus which is adjusted when the width of a fresh band exceeds or is less than the width of the preceding band in order to make sure that, regardless of the exact width of the band, its central symmetry plane invariably includes the optical axis of optical equipment at the copying station. As a rule, conventional centering apparatus comprise two flanges which are movable independently of each other into engagement with the respective edges of a band, i.e., each such flange must be adjusted independently of the other flange. Such dual adjustment consumes much time and the danger of inaccurate centering is always present, especially if the operator is careless.

Accordingly, it is an important object of the present invention to provide a novel and improved centering apparatus which can be used in connection with bands of different width and which is capable of invariably maintaining the central symmetry plane of a narrower or wider band in a predetermined plane, namely, in the plane of the optical axis if the centering apparatus is used in a photographic copying machine.

Another object of the invention is to provide a centering apparatus wherein the two flanges which engage the edges of a band need not be adjusted independently of each other so that, when needed, simultaneous adjustments of both flanges can be carried out with little loss of time.

A further object of the invention is to provide a cen tering apparatus which is capable of preventing buckling of the band.

An additional object of the invention is to provide a centering apparatus which occupies little room, wherein the flanges may be adjusted by resorting to very simple and rugged actuating means, and which can be readily installed in presently known photographic copying machines.

Still another object of our invention is to provide a centering apparatus which can properly center bands of standard width as well as such bands whose width deviates from a standard width.

A concomitant object of the invention is to provide the improved centering apparatus with novel motion transmitting means for adjusting the band-engaging flanges with reference to each other.

A further object of the invention is to provide a centering apparatus which does not scratch or otherwise damice age or deface the band and which can be installed in dark rooms to prevent exposure of light-sensitive material to undesired illumination.

Briefly outlined, one feature of our invention resides in the provision of a centering apparatus for bands of light-sensitive paper in photographic copying machines or the like. The apparatus comprises a pivot member whose axis is coplanar with the optical axis of the equipment at the copying station of the machine, a two-armed lever turnably mounted on the pivot member, guide means extending at right angles to the axis of the pivot member, and a pair of band-engaging flanges disposed at the 0pposite sides of the pivot member and each articulately connected to one arm of the lever at the same distance from the pivot member. The flanges are movable along the guide means toward and away from the pivot member into engagement with the respective edges of a band which is conveyed therebetween whereby the central longitudinal symmetry plane of the band includes the axis of the pivot member when the edges of the band are engaged by the respective flanges. The connections between the arms of the lever and the respective flanges preferably comprise links which are articulately connected with the flanges and with the respective arms, and each flange may be provided with a sleeve which is slidable along the guide means. Actuating means may be provided to shift one of the flanges toward or away from the other flange or to move the lever to a plurality of angular positions each of which corresponds to a different standard band width.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved centering apparatus itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments With reference to the accompanying drawings, in which:

FIG. 1 is a somewhat schematic fragmentary side elevational view of a photographic copying machine including a centering apparatus which is constructed and assembled in accordance With a first embodiment of our invention;

FIG. 2 is an enlarged sectional view of the centering apparatus substantially as seen in the direction of arrows from the line II-II of FIG. 1;

FIG. 3 is a view as seen in the direction of the arrow III in FIG. 2;

FIG. 4 is an axial section through a second centering apparatus; and

FIG. 5 is a transverse section as seen in the direction of arrows from the line V-V of FIG. 4.

FIG. 1 illustrates the frame 1 of a photographic copying machine. The frame 1 supports a magazine 2 for a roll 3 of convoluted band material 4 constituted by lightsensitive paper. The roll 3 is sealed against entry of light and the bottom wall of the magazine 2 has a light-tight mouth 2a for the band 4. The band is conveyed around a tensioning roll 5 and through a centering apparatus 6 which is constructed in accordance with a first embodiment of our invention. The apparatus 6 comprises a rotary deflecting cylinder 11 (see also FIGS. 2 and 3) which causes the band 4 to travel in an arcuate path so that the band is held against buckling and the width of the band remains constant. A detector roller 7 engages the concave external surface of that portion of the band 4 which passes through the centering apparatus. The roller 7 forms part of a detector unit 8 which is of known design and serves to detect the trailing end of the band 4 and to arrest the copying machine in response to such detection or to produce a visible or otherwise discernible signal which warns the personnel in charge that the supply of band stock in the magazine 2 is exhausted. The roller 7 may respond to detection of a suitable notch in the trailing end of the band 4. The entire detector unit 8 is pivotable about the axis of a horizontal supporting shaft 9 and can be rocked to and from the operative position shown in FIG. 1 by a manually operated knob 10. The supporting shaft 9 extends at right angles to the direction of lengthwise advance of the band 4.

Once moved beyond the centering apparatus 6, successive increments of the band 4 will be drawn through a copying station CS, thereupon through a marking station (not shown) at which the band is provided with imprints by resorting to a graphite wheel or the like, and finally to a collecting or convoluting station. If necessary, such convoluting station may accommodate a second centering apparatus 6 to make sure that the material of the band forms convolutions which overlie each other with a requisite degree of accuracy. Save for the construction of the centering apparatus 6, the details of the copying machine shown in FIG. 1 form no part of the present invention. This centering apparatus may be installed in a dark chamber of the frame 1 to prevent light from reaching the band 4. Only portions of the means for manipulating the apparatus 6 will extend through light-tight slots or openings in the frame 1 to permit of adjustments which are necessary when a relatively wide band 4 is followed by a narrower band, or vice versa. Of course, the apparatus 6 can be mounted in fully exposed position if it is used for centering of bands which are not sensitive to light.

The centering apparatus 6 is shown in FIGS. 2 and 3. It comprises the aforementioned deflecting cylinder 11 which is rotatable about the axis of a horizontal shaft 12. The shaft 12 is mounted in the frame 1 of the copying machine and is adjustable axially. Lock nuts 13 and 14 are provided to hold the shaft 12 in selected positions of axial adjustment. The periphery of the cylinder 11 is formed with two sets or groups of annular recesses or grooves 11a, 11b and 11d, lle. These grooves are disposed at the opposite sides of a centrally located annular groove 11c and are mirror symmetrical with reference to a central symmetry plane of the centering apparatus 6. This symmetry plane coincides with the plane subdividing the central groove llc into two identical halves and also with the longitudinal central symmetry plane of the band 4. The purpose of the apparatus 6 is to guide the band 4 in such a way that the longitudinal central symmetry plane of the band includes the optical axis of optical equipment at the copying station CS shown in FIG. 1.

A second horizontal shaft 15 is axially movably mounted in the frame 1 and can be fixed in selected positions of adjustment by a pair of lock nuts 16, 17. This shaft is telescoped into an elongated guide tube 34 which is rotatable on the shaft 15 and serves as a means for guiding two metallic band-engaging flanges 20, 21 so that the flanges are movable toward and away from each other. The flanges 20, 21 are respectively provided with cylindrical sleeves 18, 19 which are slidably guided by the tube 34. In response to turning about the axis of the shaft 15, the concave marginal portions 50 of the flanges 26, 21 can be introduced into or withdrawn from the respective grooves 11a, 11b and 11d, 11s.

The central portion of the guide tube 34 has a bore 34a for a diametrically extending pivot member 22 whose axis is located in the symmetry plane 100 and which constitutes a fulcrum for a two-armed lever 23. The two arms of the lever 23 carry pivot pins 23a, 23b which are connected with links 24, 25. The outer ends of the links 24, 25 carry pivot pins 24a, 25a which are respectively coupled to the sleeves 18, 19 of the flanges 20, 21. The distance between the pivot member 22 and pivot pins 23a, 23b is the same, and the distance between the pins 23a, 23b and pins 24a, 25a is also the same. Thus, if the lever 23 is caused to change its angular position, the flanges 29, 21 wiil be moved toward or away from each other and always through the same distance so that, when they engage the respective edges of the band 4, the central symmetry plane of the band automatically coincides with the plane 100.

The sleeves 18, 19 are coupled to each other by a resilient element, here shown as a helical contraction spring 26, which biases the flanges 20, 21 in opposite directions, i.e., this spring tends to move the flanges toward each other.

The actuating means for changing the distance be tween the flanges 20, 21. comprises a lever or arm 27 which is articulately connected with the lever 23 by means of the pivot pin 23a. The centering apparatus 6 further comprises detent means for holding the lever 23 in selected angular positions each of which corresponds to a dilferent distance between the flanges 20, 21. In the illustrated emhodiment, such detent means comprises cooperating elements respectively provided on the arm 27 and on a rocking frame 23 which can change the angular position of the guide tube 34 with reference to the shaft 15. The detent elements on the arm 27 are constituted by a series of projections or teeth 27a, 27b, 27c, 27d each of which is indicative of a different angular position of the lever 23. The detent element of the rocking frame 28 is constituted by a stop screw 28a having an eccentric tip which can be engaged by one of the projections 27a-27d at a time. A spring-biased pusher or post 29 bears against the upper side of the arm 27 to urge the underside of this arm against the tip of the stop screw 28a. By rotating the screw 28a, the operator can carry out precise adjustments in the position of the eccentric tip and in the angular position of the lever 23.

FIG. 3 illustrates the centering apparatus 6 in idle position in which the flanges 20, 21. are held away from the deflecting cylinder 11, i.e., the marginal portions 50 of these flanges are spaced from the grooves Ila-11c. If the operator then pushes the bent-over end portion 271 of the arm 27 upwardly, as viewed in FIG. 2 or 3, the post 29 is displaced against the opposition of its spring and the arm 27 can be shifted in the slot of the frame 28 to change the angular position of the lever 23, either under or against the bias of the spring 26. Rocking of the flanges 20, 21 to and from the idle positions of FIG. 3 is accomplished by turning the frame 28 and guide tube 34 about the axis of the shaft 15. Once the operator has selected a desired distance between the flanges, the frame 28 is rocked in a clockwise direction, as viewed in FIG. 3, whereby the marginal portions 50 enter selected grooves of the deflecting cylinder 11 to confine the band 4 therebetween. The marginal portions 50 are receivable in the respective grooves 11a, 11b and 11a, lle with a certain amount of clearance, and the distance between the projections 27a-27d exceeds the Width of the tip on the screw 28a so that the edges of a band 4 whose width exceeds a standard width can push the flanges 20, 21 slightly apart whereby the lever 23 insures that the movements of both flanges are invariably of the same magnitude. In other words, the band 4 can determine the ultimate distance between the flanges 20, 21 if its width exceeds a normal or standard width whereby the spring 26 insures that the flanges remain in actual contact with the respective edges of the band. Buckling of the band under the bias of the spring 26 is prevented by the cylinder 11 which guides the band in an arcuate path. Thus, the width of the band cannot change during travel between the flanges 20, 21.

The spring 26 could be replaced by a spring which would operate between one of the flanges 20, 21 and the guide tube 34 because the lever 23 and links 24, 25 insure that one of the flanges participates in movement of the other flange, or vice versa. Also, the spring 26 could be replaced by a torsion spring which biases the lever 23 in a clockwise or counterclockwise direction, depending upon whether the designer wishes to bias the flanges toward or away from each other. As a rule, the spring 26 (or an equivalent spring) will be installed in such a way that the flanges 20, 21 tend to move toward each other and to reduce the width of the band-receiving channel to a minimum value.

The number of projections 27a27d may be increased or reduced, depending upon whether the centering apparatus 6 is to be used with two, three, five or more standard band widths. The same is true for the number of grooves in the cylinder 11. For example, and when the spring 26 respectively biases the marginal portions 53 of the flanges 20, 21 against the right-hand and left-hand annular surfaces of the grooves 11a and lie, the distance between the flanges 20, 21 equals exactly the standard width of the widest band which can be centered in the apparatus 6 of FIGS. 1 to 3. If the width of the band exceeds very slightly such maximum standard width, the edges of the band will move the marginal portions away from the aforementioned annular surfaces in the grooves 11a, 11e but the band will not buckle because it is trained around the peripheral surface of the median portion of the cylinder 11.

FIGS. 4 and 5 illustrate a second centering apparatus which is more compact than the apparatus 6 of FIGS. 1 to 3. The rotary deflecting cylinder 11 of the apparatus 6 is replaced by a hollow stationary deflecting body in the form of a cylinder 30 which engages the uncoated surface of the band 4, the latter being trained around a tensioning roll 5 shown in FIG. 5. The cylinder 39 is mounted on a shaft 31 which is movable axially in the frame 101 of a photographic copying machine and can be fixed in one of several axial positions by lock nuts 113, 114. The ends of the cylinder 3i) accommodate disks 30c, 30d and the hub of the disk Stlc is fixed to the shaft 31 by radial screws 32, 33. The other disk 30d is mounted on a sleeve 38 which is coaxial with the shaft 31 but is movable axially. The central portion of the cylinder 30 has a smooth peripheral surface which comes in actual contact with the uncoated side of the band 4. The two end portions of the cylinder are provided with pairs of axially extending slots 36a, 30b.

The interior of the cylinder 30 accommodates a rotatable guide tube 35 which is provided with an axially parallel slot 35a and carries a radially extending pivot member 36 for a two-armed lever 37. The axis of the pivot member 36 is located in the longitudinal central symmetry plane of the slot 35a and also in the longitudinal central symmetry plane of the band 4.

The two disk-shaped flanges 40, 41 of the centering apparatus shown in FIGS. 4 and 5 preferably consist of sheet metal and are respectively provided with sleeves 33, 39 which are slidable on the guide tube 35, i.e., in directions at right angles to the direction of travel of the band 4. The flanges 49, 4-1 are respectively provided with projections 49a, 40b and 41a, 41b which extend outwardly through the slots 30a, 30b in the corresponding end portions of the stationary deflecting cylinder 30. Each end portion of the cylinder 30 may have a single axially parallel slot or three or more. The sleeves 38, 39 are respectively provided with radial pins 43, 44 which extend into the slot 35a of the guide tube 35 and carry links 45, 46 each of which is articulately coupled to one arm of the lever 37 on the pivot member 36. The length of both arms of the lever 37 is the same and the links 45, 46 are of identical length so that angular displacement of the lever 37 brings about identical movements of flanges 40, 41 toward or away from each other. Thus, the distance between the flange 40 and the pivot member 36 is always the same as that between the pivot member 36 and flange 41.

The central portion of the cylinder 30 is surrounded by an arcuate shield or baffle 47 which defines with the cylinder a relatively wide arcuate channel for the band 4. The width of the shield 47 is less than the minimal width of a band which is to be centered by the apparatus of FIGS. 4 and 5 so that the shield cannot unduly limit movements of the flanges 46, 4-1 toward each other.

The surfaces bounding the longitudinally extending slots a, 30b of the deflecting cylinder 30 are provided with sets or groups of notches or recesses 30e, 30f, 30g and 30h, 30i, 30/: which can accommodate the projections 40a, 40b and 41a, 41b of the flanges 40, 41 in response to rocking of such flanges about the shaft 31. It will be seen that the cylinder 30 constitutes a detent means for releasably holding the flanges 4t 41 at a selected distance from each other in response to rocking of the guide tube so that the projections a, 49b and 41a, 41b respectively extend into one of the notches 302-305; and 30h-3tlk The sleeve 38 of the flange 40 is connected to an actuating member in the form of a knob 48 which can be turned by hand to move the projections 40a, 49b and 41a, 41b into or from the respective recesses 3il*e30g and 30h-3tlk. Once the projections of the flanges 4t 41 are withdrawn from such recesses, the knob 48 may be moved axially to shift the sleeve 38 along the guide tube 35 whereby the sleeve 39 moves in the opposite direction and insures that the distance between the pivot member 36 and flange 40 changes at the same rate as the distance between the pivot member 36 and flange 41. A suitable resilient element (e.g., a torsion spring which is not shown in the drawings) is preferably provided to bias the knob 48 in a direction to maintain the projections 40a, 40b and 41a, 41b in the notches of the cylinder 30 so that, in order to change the distance between the flanges 40, 41, the operator must overcome the bias of such torsion spring. A second resilient element 42, here shown as a helical contraction spring, is connected to the flanges 40, 41 and tends to move such flanges toward each other. The spring 42 can be connected to the sleeves 39, 39 or to one of these sleeves and the guide tube 35.

FIG. 4 further shows certain details of the aforementioned detector unit 8 which is mounted on the supporting shaft 9 and can be rocked to and from operative position by the knob 10. Shaft 9 is mounted in the frame 101. The detector unit 8 may be coupled with the actuating member 48 so that it can rock about its shaft 9 in response to rocking of flanges 4t), 41 about the shaft 31. This will insure that the roller 7 of the unit 8 is moved to operative position when the marginal portions 50 extend into the notches of the cylinder 30. The baflle 47 is preferably provided with a cutout (not shown) for the roller 7 of the unit 8.

The number of notches 302-395 and 30lz-30k may be reduced to two or increased to four or more, depending on the number of standard band widths which are to be used in connection with the centering apparatus of FIGS. 4 and 5. The width of these notches preferably exceeds the width of the respective projections 49a, 40b and 41a, 41b so that the flanges 40, 41 will have some freedom of axial movement when their projections extend into selected notches in order to move apart if the width of a band exceeds a standard width. The spring 42 then insures that the flanges 40, 41 bear against the respective edges of the band.

If desired, the apparatus of FIGS. 4 and 5 may be pro vided with detent means which are indepedent of the cylinder 30.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic and specific aspects of our contribution to the art and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is:

1. Apparatus for centering bands having different widths, particularly for centering bands of light-sensitive paper in photographic copying machines, comprising a pivot member; a two-armed lever turnably mounted on said pivot member; guide means extending at right angles to the axis of said pivot member; and a pair of bandengaging flanges disposed at the opposite sides of said pivot member and each articulately connected to one arm of said lever at the same distance from said pivot member, said flanges being movable along said guide means away from and toward each other to be placed into engagement with the respective edges of a band which is conveyed therebetween whereby the central longitudinal symmetry plane of the band includes the axis of said pivot member when the flanges engage the respective edges of the band.

2. Apparatus as defined in claim 1, further comprising a pair of links each connecting one of said flanges with the respective arm of said lever.

3. Apparatus as defined in claim 1, further comprising deflecting means for guiding the band in an arcuate pa-th intermediate said flanges.

4. Apparatus as defined in claim 3, wherein said deflecting means comprises a cylinder rotatable about an axis which is normal to the axis of said pivot member.

5. Apparatus as defined in claim 4, wherein the axis of said cylinder is parallel to said guide means.

6. Apparatus as defined in claim 5, wherein said cylinder has two groups of circumferential grooves disposed in mirror symmetry with reference to said plane, said flanges being rockable about an axis which is parallel to the axis of said cylinder and having concave portions movable into and from the grooves of the respective groups in response to rocking of said flanges.

7. Apparatus as defined in claim 1, wherein said flanges consist of sheet metal.

8. Apparatus as defined in claim 1, further comprising actuating means for moving said flanges with reference to said guide means.

9. Apparatus as defined in claim 8, wherein said actuating means comprises a manually operable member articulately connected to one arm of said lever.

10. Apparatus as defined in claim 9, further comprising detent means for releasably holding said manually operable member in a plurality of positions each of which corresponds to a difierent distance between said flanges.

11. Apparatus as defined in claim 10, wherein said detent means is arranged to maintain said manually operable member in each of said positions with a small clearance to allow for some movement of said flanges relative to said guide means.

12. Apparatus as definedin claim 11, further comprising resilient means for biasing said flanges in opposite directions.

13. Apparatus as defined in claim 12, wherein said resilient means is arranged to bias said flanges toward said pivot member so that the flanges bear against the respective edges of a band whose width exceeds one of said different distances between said flanges.

14. Apparatus as defined in claim 1, further comprising resilient means for biasing said flanges in opposite directions.

15. Apparatus as defined in claim 1, further comprising detector means for tracking the band intermediate said flanges, means for supporting said detector means, and means for rocking said detector means about a secnd axis which is normal to the axis of said pivot member to move said detector means into and from engagement with the band.

16. Apparatus as defined in claim 15, wherein said 35 guide means is rockable with said flanges about an axis which is parallel with said second axis.

'17. Apparatus as defined in claim 1, further comprising stationary deflector means for guiding the band in an arcuate path intermediate said flanges, said deflector means comprising a hollow body surrounding said pivot member and said two-armed lever.

18. Apparatus as defined in claim 17, wherein said hollow body is constituted by a cylinder and said guide means is coaxial with said cyinder, said cyinder comprising two end portions each having at least one axially parallel slot and each of said flanges having a bandengaging projection extending outwardly through the slot .of one of said end portions.

19. Apparatus as defined in claim 18, wherein each of said flanges is constituted by a disk having a sleeve which is slidably telescoped onto said guide means, said guide means being fixedly connected with said pivot member.

20. Apparatus as defined in claim 19, further comprising a pair of Jinks each connecting one of said sleeves wit-h the respective arm of said lever.

21. Apparatus as defined in claim 19, wherein said guide means is provided with a groove extending in parallelism with the axis of said cylinder and wherein each of said sleeves comprises a pin extending into said groove to hold the sleeves against rotation withv reference to said guide means.

22. Apparatus as defined in claim 21, further comprising a pair of links each connecting one of said pins with one arm of said lever.

23. Apparatus as defined in claim "19, wherein said guide means is rotatable about the axis of said cylinder.

24. Apparatus as defined in claim 18, wherein said guide means is fixedly connected to said pivot member and is turnable with said flanges about the axis of said cylinder, and further comprising actuating means operatively connected with said guide means to rotate such guide means about the axis of said cylinder.

25. Apparatus as defined in claim 24, wherein said actuating means comprises :a knob aflixed to one of said flanges.

26. Apparatus as defined in claim 1, wherein said guide means is turnable with said flanges about a second axis which is normal to the axis of said pivot member, and further comprising .detent means for releasably holding said flanges at different distances from each other, said flanges being turnable about said second axis into and from engagement with said detent means.

27. Apparatus as defined in claim 26, wherein said detent means comprises a stationary cylinder surrounding said guide means and said flanges and having two end portions each provided with at least one slot parallel to said second axis and a plurality of notches communicating with each of said slots, said flanges having band-engaging projections each extending outwardly through one of said slots and being movable into and from a selected notch in response to rocking of said guide means.

References Cited UNITED STATES PATENTS 2,065,383 12/1936 Lloyd et al 226-199 2,524,582 10/1950 Yerkes 226-199 3,061,303 '10/1962 Glaser et a1 226-199 X 3,119,534 l/1964 Lehnert 226-199 X 3,227,346 1/1966 OBrien 226-199 X 3,269,627 8/1966 OBrien 226-199 X ALLEN N. KNOWLES, Primary Examiner. 

1. APPARATUS FOR CENTERING BANDS HAVING DIFFERENT WIDTHS, PARTICULARLY FOR CENTERING BANDS OF LIGHT-SENSITIVE PAPER IN PHOTOGRAPHIC COPYING MACHINES, COMPRISING A PIVOT MEMBER; A TWO-ARMED LEVER TURNABLY MOUNTED ON SAID PIVOT MEMBER; GUIDE MEANS EXTENDING AT RIGHT ANGLES TO THE AXIS OF SAID PIVOT MEMBER; AND A PAIR OF BANDENGAGING FLANGES DISPOSED AT THE OPPOSITE SIDES OF SAID PIVOT MEMBER AND EACH ARTICULATELY CONNECTED TO ONE ARM OF SAID LEVER AT THE SAME DISTANCE FROM SAID PIVOT MEMBER, SAID FLANGES BEING MOVABLE ALONG SAID GUIDE MEANS AWAY FROM AND TOWARD EACH OTHER TO BE PLACED INTO ENGAGEMENT WITH THE RESPECTIVE EDGES OF A BAND WHICH IS CONVEYED THEREBETWEEN WHEREBY THE CENTRAL LONGITUDINAL SYMMETRY PLANE OF THE BAND INCLUDES THE AXIS OF SAID PIVOT MEMBER WHEN THE FLANGES ENGAGE THE RESPECTIVE EDGES OF THE BAND. 